The disclosure herein relates generally to flow rack systems and more particularly to a gravity flow rack with a reverse flow limiting device.
Gravity flow racks are often used in warehouse and manufacturing environments. They provide an effective solution for transporting, storing and dispensing packaged and containerized goods. They are preferred in many applications because they reduce floor space, decrease restocking time and provide for a more efficient flow of goods through a work stream.
A typical gravity flow rack includes a frame with a plurality of flow rails mounted to the frame. The flow rack has a front end where items are removed from the flow rack and a back end where items are placed onto the flow rails. The flow rails are spaced apart and mounted at a downward angle such that the ends of the flow rails adjacent to the front end of the flow rack are at a lower elevation than the end of the flow rails adjacent to the back end of the flow rack. The items that are closest to the front of the flow rack rest under the force of gravity against a retention member that is attached to the flow rack adjacent to the front end.
U.S. Pat. No. 4,681,203 discloses an un-driven gravity roller conveyor in which a plurality of discrete, elongate channel members are attached in a spaced-apart, parallel relationship to a base structure. The separation between neighboring channel members is made equal to the separation between the opposite side walls of each channel member, thereby providing a plurality of rows extending between the side walls of the channel members. Open slots equidistantly spaced apart are formed along the upper edges of each side wall. The slots are aligned in parallel columns substantially perpendicular to the length of the rows. Load-bearing rollers mounted upon axles are arranged in rows both between the opposite side walls in each channel member and between adjacent side walls of neighboring pairs of channel members, with the axles of the rollers held within the slots. The spacing between slots is substantially less than one-half of the exterior diameter of the rollers.
U.S. Pat. No. 4,541,518 discloses a material flow rail construction of the type employed to transport containers or articles from one location to another using the force of gravity. The improved material flow rail comprises a substantially U-shaped channel within which a multiplicity of mounting bolts is attached. Individual bearing assemblies are placed on the mounting bolts. By placing the individual bearing assemblies closely adjacent one another in a longitudinal direction with respect to the support channel, the flow rail has the ability to transport parts having very small "footprint" areas because a large space between rollers is not presented for parts or components thereof to become caught. By providing a loose fit between the bearing inner races and the supporting mounting bolts, the inner race is permitted to rotate slightly with respect to the mounting bolts thereby presenting new wear surfaces as the flow rail is put into use. Additionally, a loose fit may be provided between the mounting bolts and the support channel to permit the latter to rotate with respect to the former, also presenting new wear surfaces.
U.S. Pat. No. 4,168,780 discloses a storage rack structure of the gravity feed type having inclined storage racks carried between front and rear vertical standards. Items such as pallets, carrying cases and the like are loaded from the rear for gravity feed to the front. The flow rails are hung within a channel of a front facing rail having a back web providing an abutment for stopping the pallets, and include a raised abutment at the rear end thereof providing a fulcrum about which each pallet initially impacts and pivots for loading onto the flow rail.
U.S. Pat. No. 3,915,275 discloses a set of constructional elements which may be combined to define conveyor devices, such as roller trains, continuously running shelves, and band conveyors, etc. The set of constructional elements includes elongated, generally U-shaped support frames having slit and T-shaped recesses therein, and cooperating fittings adapted to be inserted into the slits and capable of supporting the roller elements. The constructional elements may be assembled in varied configurations to define the desired conveyor device.
A common problem with flow racks is that a container full of items, some of them fragile and expensive, may be pushed off the back end of the flow rack when containers are stacked along the entire length of the flow rails. This typically occurs when the frontmost container is being removed. To remove the front container, the front container and any containers stacked behind the front container must be pushed in a reverse direction to release the frontmost container from against the retention member. If a container is too close to the back end of the rack and it is pushed back far enough, it will fall off of the flow rack. This can result in damage to the items in the fallen container.
Accordingly, a need has arisen for a flow rack including a reverse flow limiting device that overcomes the shortcomings of previous flow rack constructions and techniques.